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arXiv · 2008.02414

Pseudospin symmetry and octupole correlations for multiple chiral doublets in 131Ba

Y. P. Wang·Y. Y. Wang·J. Meng
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Abstract

A reflection-asymmetric triaxial particle rotor model with three quasiparticles and a reflection-asymmetric triaxial rotor is developed, and applied to investigate the observed multiple chiral doublets (M\c{hi}D) candidates with octupole correlations in 131Ba, i.e., two pairs of positive-parity bands D3-D4 and D5-D6, as well as one pair of negative-parity bands D7-D8. The energy spectra, the energy staggering parameters, the B(M1)/B(E2) ratios, and the B(E1)/B(E2) ratios are reproduced well. The chiral geometries for these M\c{hi}D candidates are examined by the azimuthal plots, and the evolution of chiral geometry with spin is clearly demonstrated. The intrinsic structure for the positive-parity bands is analyzed and the possible pseudospin-chiral quartet bands are suggested.

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Y. P. Wang, Y. Y. Wang, J. Meng. 2020-08-06. Pseudospin symmetry and octupole correlations for multiple chiral doublets in 131Ba. https://doi.org/10.1103/physrevc.102.024313

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